In recent memory, women’s Wimbledon titles have left little gray area to be discussed — the Williams sisters have won six of the last eight singles’ trophies. Serena, right, and Venus advanced to the quarterfinals with victories Monday.

WIMBLEDON, England — Wimbledon has already lost its top four seeded women’s players, while the Williams sisters keep rolling toward another sibling final. Roger Federer and Rafael Nadal are also closing in on another title matchup.

Monday’s fourth-round play at the All England Club produced more upsets at the top of the women’s seedings but also offered more convincing wins from the champions and title contenders.

With top-seeded Ana Ivanovic and No. 3 Maria Sharapova eliminated last week, none of the top four seeded women reached the quarterfinals — the first time that’s happened at Wimbledon and also the first time at any Grand Slam tournament in the 40-year history of the Open era.

The highest women’s seeded player left is No. 5 Elena Dementieva, who cruised to a 6-2, 6-1 win over Shahar Peer. Only three of the top 14 seeded women remain. The other two are the Williams sisters, and they posted back-to-back wins on Court 2.

Defending champion and seventh-seeded Venus Williams beat Russian teenager Alisa Kleybanova 6-3, 6-4, while two-time winner and No. 6 Serena downed Bethanie Mattek — the only other American left in the men’s or women’s draw — 6-3, 6-3. Later, the sisters made it 3-0 on Court 2 for the day, beating Anabel Medina Garrigues and Virginia Ruano Pascal 6-1, 6-4 to reach the quarters of the women’s doubles.

The sisters are in opposite halves of the draw and could meet in the final Saturday.

In men’s play, Federer swept Lleyton Hewitt — the last man to win the title before Federer’s run of five straight titles — 7-6 (7), 6-2, 6-4 on Centre Court to extend his winning streak on grass to 63 matches and 38 in a row at the All England Club. Federer will next face the last player to beat him on grass and at Wimbledon — Croatian Mario Ancic, who won in the first round in 2002. Ancic beat Fernando Verdasco 3-6, 4-6, 6-3, 6-4, 13-11.

WASHINGTON — Thirty games into the 82-game NHL season, and nearly six weeks after the Matt Duchene trade, Avalanche general manager Joe Sakic discussed the state of his team before Tuesday’s 5-2 loss at the Washington Capitals.